Perret tower

The Perret tower, originally called La tour pour regarder les montagnes, is an observation tower located in Grenoble, in the Paul Mistral public park. It is the first tower built in reinforced concrete in Europe. In 1998, it was officially declared to be a national heritage site. It was built for the International Exhibition of Hydropower and Tourism where it was the orientation tower and the symbol of the exhibition. Nowadays, it is the last vestige of this exhibition.

Source: Wikipedia